Data repositories and in particular, databases are computerized information storage and retrieval systems. A database query refers to a set of commands or clauses for retrieving data stored in the databases. Queries may come from users, application programs, or remote systems. A query may specify a specific location, such as, a table or a column in a database to retrieve data from, how to join columns from multiple tables, and conditions that must be satisfied for a particular data record to be included in a query result set. Current structured data, typically relational databases, process queries composed in an exacting format specified by a query language. For example, the widely used Structured Query Language (SQL) is supported by many relational databases.
There are many disciplines that rely on databases, such as life sciences, require increasingly complex databases and database queries. Running large or complex query typically uses multiple resources and has been a subject of study and interest.